Add 7/12 and 9/21
7/12 + 9/21 is 85/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
7/12 = 7 × 7/12 × 7 = 49/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
9/21 = 9 × 4/21 × 4 = 36/84 - Add the two like fractions:
49/84 + 36/84 = 49 + 36/84 = 85/84 - So, 7/12 + 9/21 = 85/84
In mixed form: 11/84
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